"This article is all about "perception," and pays scant attention to GE polling in making the contention that only Clinton could defeat Giuliani and the other Republican front-runners. Rasmussen GE polls have rather consistently shown Edwards to have the best chance against the Republican contenders. These polls are routinely ignored in the media."

I think the key point you're missing in from the article is who has the best chances of defeating the Republicans in the election not as a matter of polling but as in response the behavior of the Republicans. The inevitability factor is not static but rather the dynamic notion that Clinton (possibly Edwards and Obama as well) but specifically Clinton has been able to beat Republicans and win them over and can deal what they throw at her. Versus Edwards who may or may not have that ability and in polling can win but whose outcome through an election cycle is untested especially with candidates of this magnitude.